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United States Patent | 5,528,255 |
Hagimori | June 18, 1996 |
A display control device for a level meter, including a BPF for performing a band-pass filtering of an audio signal to obtain a plurality of frequency components. The BPF obtains an average level of each frequency component of the audio signal. A variable resistor divides a power source voltage. An A/D converter converts the frequency components of the audio signal, the average level and the divided voltage into digital signals. A display controller displays the levels of the frequency components and the average levels thereof on an LCD. The display controller holds a peak value of one of the frequency components or the average levels thereof, and the peak hold time is determined on the basis of the divided voltage. The peak hold time can be freely changed depending on tastes and uses of users.
Inventors: | Hagimori; Haruo (Kyoto, JP) |
Assignee: | Rohm Co., Ltd. (Kyoto, JP) |
Appl. No.: | 981008 |
Filed: | November 24, 1992 |
Dec 06, 1991[JP] | 3-322990 |
Current U.S. Class: | 345/35; 381/56 |
Intern'l Class: | G01D 007/00 |
Field of Search: | 340/815.11,752,753,754,722 381/98,56 345/140,158,35,36,37,38,39 84/464 R,464 A 455/157.2,159.1,177.1,200.1,344 |
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5204969 | Apr., 1993 | Capps et al. | 381/48. |
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